There are two verbs in Spanish which are translated as “to be” in English. They each have very specific uses, and the use of one or another will have a significant impact on meaning. Using the wrong verb can render your sentence utterly meaningless, or may result in an unintended mistatement.
Many textbooks create long lists of cases in which one uses ser or estar. The reality is that the difference can be essentially reduced to the difference between a description of the inherent characteristic of an object, vs. the state or condition of being of that object. The detailed breakdowns on usage can all ultimately be reduced to the above difference. The following breakdown is brief, but relatively complete:
